Detective Chief Inspector Nick Scola, of the Metropolitan Police appealed for anyone who may have witnessed the incident.

He said: "I believe the victim had attended a party in Albon House.

"I need to trace everyone at that party, and in particular I am appealing for any information about a group of between five and eight males seen running from the scene into the surrounding streets and possibly through King George's Park."

A number of people have been arrested and are currently in custody, reports the Evening Standard.

Police cordoned off a stretch of road outside Albon House today as forensics teams examined the scene.

Jessica Cremin, 19, who lives nearby, said: "I have a lot of younger cousins and brothers and sisters that I take out to the park, so obviously now I'm going to be more aware of what's going on.

"It's really frightening. When I heard this had happened I had shivers down all over my body and I was shaking. It's so scary."